In some applications involving wireless devices such as a cellular telephone, it is desirable to restrict the calls—whether the call is voice or data—that can be placed or received. For example, a Firefly™ cellular telephone is designed to be used by children and has limited functionality for a child to place or receive calls. Typically, a parent adds a number of a party the child is permitted to call to an internal phone book. The phone usually has one or more buttons that allow the child to place a call to the stored number, but does not provide a means for dialing numbers that are not stored in the phone book. In addition, the parent may select an option whereby the phone will reject an incoming call that is not from one of the stored numbers. Thus, the child can be restricted to placing calls to and receiving calls from parties who are “approved” by the parent or emergency services (e.g., 911).
Conventionally, the phone book and call restrictions are stored in and maintained by the hardware in the device. Thus, the restrictions are specific to the device itself. If the device's Subscriber Identity Module (SIM) card, which contains the user account information necessary to activate the device, is removed and placed into another compatible device, the new device will not be restricted to the numbers in the phone book. This, technically sophisticated children may be able to bypass their parent's restrictions by placing the SIM card into another device.
A device that has the functionality of the SIM card built-in (i.e., manufactured as part of the hardware of the device and therefore incapable of being removed without causing damage to the device) could address this issue. Unfortunately, manufacturing customized devices that have integrated SIM functionality could be more expensive than manufacturing a device that uses a standard SIM card. It may also be desirable to allow the user to move the SIM card from one device to another for interoperability or upgrade purposes. In addition, manufacturing a SIM card that could itself store the restrictions would most likely be significantly more expensive than using a standard SIM card.
Other situations also may involve restricted calling. For example, a company that issues telephones to its employees for certain tasks may wish to restrict calls to a certain geographic area, work-related parties, emergency services, etc. In addition, the company may wish to limit data transfers—such as text messages, audio or video information, or other types of data—to approved parties.
The Global System for Mobile communication standard (GSM) provides (using a standard called “Fixed Dialing Number” (FDN)) for a device feature that enables restrictions to be placed on outgoing calls. The restrictions may be placed using a “wildcard” setting, such as 404-236-****, where a call may be placed to any number that begins with the 404 area code and 236 prefix. The restrictions, however, are limited to a GSM-compliant device that has a SIM card (or Universal Integrated Circuit Card) that supports FDNs and has the feature turned on. In addition, the restrictions are only for outgoing calls; incoming calls are unaffected.
As noted above, device-based restrictions have significant drawbacks in that a sophisticated user can circumvent the restrictions by removing the SIM card and using another device. A network-based restriction would eliminate this problem by associating the restrictions with a user's account, which will always be effective regardless of which device the user is using. A conventional mechanism for establishing a network-based calling restriction involves international dialing. Typically, a cellular service provider has a default setting that does not allow a cellular telephone to dial international numbers. If a user wishes to make such calls, the user must contact a customer service representative of the cellular service provider and request the change. Because the international calling restriction is network-based it is independent of the device being used. For example, if a user removes the SIM card from his or her phone and inserts it into another phone, the restrictions will still be in place because the network will still access the user's account to check for any calling restrictions. Requiring the user to contact a customer service representative, however, is very inconvenient for most users, especially if the user wishes to create a list of approved numbers for incoming and/or outgoing calls. In such a case, the user would be forced to have a lengthy conversation with the customer service representative to enter all of the approved numbers, and would have to call in again every time the user wished to revise the numbers.
Thus, it can be seen a need exists for a user to have the ability to more easily place restrictions on incoming and/or outgoing calls in a network-based and device-independent manner. The present invention addresses this need.